Rename [config.]cxx.header_units to importable_headers

7 files changed, 31 insertions, 26 deletions

diff --git a/build2/c/init.cxx b/build2/c/init.cxx
index 6944680..dbaff78 100644
--- a/build2/c/init.cxx
+++ b/build2/c/init.cxx
@@ -168,7 +168,7 @@ namespace build2
         v.insert<strings> ("config.c.coptions", true),
         v.insert<strings> ("config.c.loptions", true),
         v.insert<strings> ("config.c.libs",     true),
-        nullptr          /* config.c.header_units */,
+        nullptr          /* config.c.importable_headers */,
 
         v.insert<process_path> ("c.path"),
         v.insert<dir_paths>    ("c.sys_lib_dirs"),
@@ -178,7 +178,7 @@ namespace build2
         v.insert<strings>      ("c.coptions"),
         v.insert<strings>      ("c.loptions"),
         v.insert<strings>      ("c.libs"),
-        nullptr               /* c.header_units */,
+        nullptr               /* c.importable_headers */,
 
         v["cc.poptions"],
         v["cc.coptions"],
diff --git a/build2/cc/common.hxx b/build2/cc/common.hxx
index f9f13c1..dec71ed 100644
--- a/build2/cc/common.hxx
+++ b/build2/cc/common.hxx
@@ -47,7 +47,7 @@ namespace build2
       const variable& config_x_coptions;
       const variable& config_x_loptions;
       const variable& config_x_libs;
-      const variable* config_x_header_units;
+      const variable* config_x_importable_headers;
 
       const variable& x_path;         // Compiler process path.
       const variable& x_sys_lib_dirs; // System library search directories.
@@ -57,7 +57,7 @@ namespace build2
       const variable& x_coptions;
       const variable& x_loptions;
       const variable& x_libs;
-      const variable* x_header_units;
+      const variable* x_importable_headers;
 
       const variable& c_poptions; // cc.*
       const variable& c_coptions;
@@ -140,7 +140,7 @@ namespace build2
       bool modules;                 // x.features.modules
       bool symexport;               // x.features.symexport
 
-      const strings* hdr_units;     // x.header_units (NULL if unused/empty)
+      const strings* import_hdr;    // x.importable_headers (NULL if unused/empty).
 
       const dir_paths& sys_lib_dirs; // x.sys_lib_dirs
       const dir_paths& sys_inc_dirs; // x.sys_inc_dirs
@@ -210,7 +210,7 @@ namespace build2
             tstd (std),
             modules (fm),
             symexport (fs),
-            hdr_units (nullptr),
+            import_hdr (nullptr),
             sys_lib_dirs (sld), sys_inc_dirs (sid),
             sys_lib_dirs_extra (sle), sys_inc_dirs_extra (sie),
             x_src (src), x_mod (mod), x_hdr (hdr), x_inc (inc) {}
diff --git a/build2/cc/compile-rule.cxx b/build2/cc/compile-rule.cxx
index 07677a9..dd38945 100644
--- a/build2/cc/compile-rule.cxx
+++ b/build2/cc/compile-rule.cxx
@@ -877,8 +877,8 @@ namespace build2
           if (ut == unit_type::module_iface)
             cs.append (&md.symexport, sizeof (md.symexport));
 
-          if (hdr_units != nullptr)
-            hash_options (cs,  *hdr_units);
+          if (import_hdr != nullptr)
+            hash_options (cs,  *import_hdr);
 
           if (md.pp != preprocessed::all)
           {
@@ -2003,11 +2003,11 @@ namespace build2
           {
             // See if we need to translate this include to import.
             //
-            if (hdr_units != nullptr)
+            if (const strings* ih = import_hdr)
             {
-              auto i (lower_bound (hdr_units->begin (), hdr_units->end (), hp));
+              auto i (lower_bound (ih->begin (), ih->end (), hp));
 
-              if (i != hdr_units->end () && *i == hp)
+              if (i != ih->end () && *i == hp)
               {
                 // Doesn't seem there is much use in trying to correlate the
                 // followup in this case; what else can the compiler import?
diff --git a/build2/cc/module.cxx b/build2/cc/module.cxx
index a8f25c6..20e39a8 100644
--- a/build2/cc/module.cxx
+++ b/build2/cc/module.cxx
@@ -463,20 +463,20 @@ namespace build2
       rs.assign (x_libs) += cast_null<strings> (
         config::optional (rs, config_x_libs));
 
-      // config.x.header_units
+      // config.x.importable_header
       //
       // It's still fuzzy whether specifying (or maybe tweaking) this list in
       // the configuration will be a common thing to do so for now we use
       // omitted. It's also probably too early to think whether we should have
       // the cc.* version and what the semantics should be.
       //
-      if (x_header_units != nullptr)
+      if (x_importable_headers != nullptr)
       {
-        lookup l (config::omitted (rs, *config_x_header_units).first);
+        lookup l (config::omitted (rs, *config_x_importable_headers).first);
 
         // @@ MODHDR: if(modules) ?
         //
-        rs.assign (x_header_units) += cast_null<strings> (l);
+        rs.assign (x_importable_headers) += cast_null<strings> (l);
       }
 
       // Load cc.core.config.
@@ -503,20 +503,20 @@ namespace build2
       if (!cast_false<bool> (rs["cc.core.loaded"]))
         load_module (rs, rs, "cc.core", loc);
 
-      // Process, sort, and cache (in this->hdr_units) the header units list.
+      // Process, sort, and cache (in this->import_hdr) importable headers.
       // Keep the cache NULL if unused or empty.
       //
       // @@ MODHDR TODO: translate <> to absolute paths.
       // @@ MODHDR TODO: support exclusions entries (e.g., -<stdio.h>)?
       //
-      if (modules && x_header_units != nullptr)
+      if (modules && x_importable_headers != nullptr)
       {
-        strings* v (cast_null<strings> (rs.assign (x_header_units)));
+        strings* v (cast_null<strings> (rs.assign (x_importable_headers)));
 
         if (v != nullptr && !v->empty ())
         {
           sort (v->begin (), v->end ());
-          hdr_units = v;
+          import_hdr = v;
         }
       }
 
diff --git a/build2/cc/types.hxx b/build2/cc/types.hxx
index 4403e4c..60c9a34 100644
--- a/build2/cc/types.hxx
+++ b/build2/cc/types.hxx
@@ -21,7 +21,12 @@ namespace build2
     //
     // Note that our terminology doesn't exactly align with the (current)
     // standard where a header unit is not a module (that is, you either
-    // import a module unit or a header unit).
+    // import a "module [interface translation unit]" or a "[synthesized]
+    // header [translation] unit"). On the other hand, lots of the underlying
+    // mechanics suggest that a header unit is module-like; they end up having
+    // BMIs (which stand for "binary module interface"), etc. In a sense, a
+    // header unit is an "interface unit" for (a part of) the global module
+    // (maybe a partition).
     //
     enum class unit_type
     {
diff --git a/build2/cxx/init.cxx b/build2/cxx/init.cxx
index 3fb636f..a04a30a 100644
--- a/build2/cxx/init.cxx
+++ b/build2/cxx/init.cxx
@@ -394,16 +394,16 @@ namespace build2
         v.insert<strings> ("config.cxx.loptions", true),
         v.insert<strings> ("config.cxx.libs",     true),
 
-        // List of modular headers. Inclusion of such headers is translated to
-        // the corresponding header unit imports.
+        // List of importable headers. Inclusion of such headers is translated
+        // to the corresponding header unit imports.
         //
         // A header can be specified either as an absolute and normalized path
         // or as a <>-style include name. The latter kind is automatically
         // translated to the absolute form based on the include search paths
         // extracted from the compiler. Note also that all entries must be
-        // specified before loading the module.
+        // specified before loading the cxx module.
         //
-        &v.insert<strings> ("config.cxx.header_units", true),
+        &v.insert<strings> ("config.cxx.importable_headers", true),
 
         v.insert<process_path> ("cxx.path"),
         v.insert<dir_paths>    ("cxx.sys_lib_dirs"),
@@ -413,7 +413,7 @@ namespace build2
         v.insert<strings>  ("cxx.coptions"),
         v.insert<strings>  ("cxx.loptions"),
         v.insert<strings>  ("cxx.libs"),
-        &v.insert<strings> ("cxx.header_units"),
+        &v.insert<strings> ("cxx.importable_headers"),
 
         v["cc.poptions"],
         v["cc.coptions"],
diff --git a/tests/cc/modules/headers.testscript b/tests/cc/modules/headers.testscript
index c6f16b7..4b8067f 100644
--- a/tests/cc/modules/headers.testscript
+++ b/tests/cc/modules/headers.testscript
@@ -26,6 +26,6 @@ cat <<EOI >=driver.cxx;
   #endif
   int main () {return f () - CORE_OUT;}
   EOI
-$* test clean config.cxx.header_units="$~/core.hxx" &$~/../build/cc/*** <<EOI
+$* test clean config.cxx.importable_headers="$~/core.hxx" &$~/../build/cc/*** <<EOI
   exe{test}: cxx{driver}
   EOI